1. Field of the Invention
The present invention relates to network management in communication networks, and more specifically to a method and apparatus for explicit locking of resources in a device accessible on a network.
2. Related Art
Networks are generally implemented to connect user devices (e.g., servers, personal computers). The connectivity enables implementation of various applications. For some of the applications, the network elements (e.g., routers, bridges, gateways) also operate as user devices. Thus, the word devices is generally used to refer to, among others, both user devices and network elements.
Devices generally contain several resources (e.g., routing table, passwords, SNMP community string, VPN configuration), and often need to be locked. Locking generally refers to prevention of access to at least some of the devices. As is well known, locking is often used associated with write operations (or modification in general), in which exclusive access is provided to a writing device at least until the writing operation (or modification) is complete.
Such locking feature may be necessary in devices accessible on a network as well. In one example scenario, an application in a network management station (NMS) may need to change the configuration (e.g., the routing table) of a device. At least during such configuration, it may be desirable to ensure that exclusive access of device (or routing table) is provided to the application. Accordingly, locking feature may be desirable in devices accessible on a network.
In one prior approach, a NMS maintains an internal table indicating the external resources which are to be locked, and an application may request a lock of a desired resource. A lock is granted to such a requesting application, and other applications executing in the NMS are denied access to the same resource while the table indicates that the resource is locked. As a result, at least the other applications in the NMS are denied access to the resource.
One problem with such an approach is that the lock indication in the NMS may not prevent applications in some other devices (e.g., another NMS) from accessing and modifying the same resource. As an environment may contain many NMSs, two applications in different NMSs may attempt to configure (modify) the same resource.
As would be readily appreciated, such modification attempts by multiple NMSs leads to absence of predictability in terms of expected end results (since the result may depend on which NMS modified last), in addition to potentially raising questions of integrity of the configuration of the resource.
In the drawings like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The drawing in which an element first appears is indicated by the leftmost digit(s) in the corresponding reference number.